Trends & issues in crime and criminal justice no.440

Foreword | Up to 30 percent of children experience childhood sexual abuse (CSA) and whether this impacts re-victimisation or offending as an adult has been the subject of numerous studies.

This study investigates whether a disproportionate number of CSA victims subsequently perpetrate offences and experience future victimisation compared with people who have not been sexually abused. In a sample of 2,759 CSA victims who were abused between 1964 and 1995, it was found CSA victims were almost five times more likely than the general population to be charged with any offence than their non-abused counterparts, with strongest associations found for sexual and violent offences. CSA victims were also more likely to have been victims of crime, particularly crimes of a sexual or violent nature.

This research highlights the need for therapeutic interventions targeted at adolescent male CSA victims, particularly with regard to offender treatment programs, where many programs currently do not allow for exploration of offenders’ own sexual victimisation.

Adam TomisonDirector

Childhood sexual abuse (CSA) continues to occur in our communities at an alarming rate, with up to 30 percent of children experiencing CSA of any kind and between five and 10 percent experiencing severe abuse (Fergusson & Mullen 1999). CSA has been associated with an array of emotional, behavioural and social difficulties (Cutajar et al. 2010a, 2010b; Fergusson & Mullen 1999; Gilbert et al. 2009). Of considerable interest is the relationship between CSA, offending and re-victimisation, particularly sexual offending re-victimisation. Existing studies that have investigated these relationships have suffered from a lack of empirical sophistication, which has left a large gap in our understanding of the fundamental questions pertaining to how many sexually abused children later offend or experience re-victimisation. In particular, most studies have been marred by small samples, have relied upon adults’ self-reports of CSA, have included samples with relatively few males and the follow-up of offending and victimisation has often been based upon self-report.

Subsequent offending by childhood sexual abuse victims

Retrospective self-report studies of child sex offenders indicate up to 75 percent report a history of CSA, with Hanson and Slater’s (1988) review of 18 studies showing that 33 percent of perpetrators reported experiencing CSA (Johnson et al. 2006). The reported rates are higher than the 10–20 percent of males in the general population who experience CSA (Fergusson & Mullen 1999). By contrast, a meta-analysis of studies comparing the self-reported sex abuse histories of sex offenders and others found that the most studies did not find a significant difference between groups in reporting histories of sexual abuse (Jespersen, Lalumiere & Seto 2009).

In an Australian study (Nathan & Ward 2002) with a very small sample size, 75 percent of the 12 female sex offenders examined for a pre- or post-release evaluation reported a history of CSA. Other studies have found that female sexual offenders reported experiencing CSA at a higher frequency than other female offenders, male sex offenders and non-sex offending female students (Fromuth & Conn 1997; Kaplan & Green 1995; Mathews, Hunter & Vuz 1997; Miccio-Fonseca 2000; Pothast & Allen 1994).

Siegel and Williams (2003a) compared 206 cases of sexually abused girls with 205 matched cases of non-abused girls. The samples were obtained from hospital emergency room records of females aged up to 12 years who were sexually abused between 1973 and 1975 (67% penetration) and same-aged girls who were not sexually abused. Official offence histories obtained in 1995 (20 years later) revealed that victims (20.4%) were significantly more likely than controls (10.7%) to have been arrested as adults. Sex offences were not identified or studied separately.

Widom and Ames (1994) studied 908 substantiated cases of children who were abused between 1967 and 1971 and matched the sample to 667 non-abused cases. They followed up all subjects through arrest records in 1988 and 1994 (Widom & Maxfield 2001). Abused children were victimised prior to the age of 11 years; with abuse consisting of physical abuse, neglect and/or sexual abuse (125 of the cases, 84% girls). A higher proportion of abused than non-abused cases were arrested as a juvenile (27% vs 17%) or an adult (42% vs 33%; Widom & Maxfield 2001). More males than females in both groups were arrested for violent offences (including rape and sodomy); however, a significant difference was only established for abused females relative to their non-abused counterparts. In an earlier study, however, Widom and Ames (1994) found 3.9 percent of abused children compared with 0.4 percent of controls were arrested for a violent sex crime and this was largely attributed to the physically abused group.

Subsequent victimisation of childhood sexual abuse victims

In addition to offending, sexual re-victimisation of CSA victims has also been studied (Beitchman et al. 1992; Noll 2005; Roodman & Clum 2001). Results indicate that males and females who report an adult experience of sexual assault, or interpersonal violence, were more likely to report a history of CSA than those who did not report such abuse (Briere & Elliott 2003; Elliott, Mok & Briere 2004).

An Australian study of 183 substantiated cases of CSA followed up six years later revealed that 17 percent of youth had notifications of further CSA (Swanston et al. 2002). An American study followed up and interviewed 74 confirmed intrafamilial female CSA victims seven years after their initial assessment and found 20.9 percent reported experiencing rape or sexual assault compared with 10 percent of comparisons (Noll et al. 2003), although this difference did not reach statistical significance. However, CSA victims were significantly more likely (1.6 times) to be the victim of a physical assault. In an extension of Siegel and Williams’ (2003b) study on 206 CSA female victims, 84 victims and 84 comparisons were interviewed up to 24 years later. There were no differences between the abused and comparison groups in self-reporting of sexual assault in adolescence (28.7% vs 24.1%) or adulthood (48.3% vs 37.9%); however, a third of the comparison group had also been sexually abused in childhood.

These findings suggest that many female CSA victims are subsequently victimised; however, due to the limited and flawed prospective studies it cannot be concluded that CSA among female victims poses an increased risk factor for later sexual assault.

The present study

The primary aim of this study is to examine the relationship between CSA and subsequent criminal offending and victimisation. This study overcomes many limitations of previous studies by conducting a follow-up study of a large sample of both male and female victims, whose sexual abuse was confirmed, with a matched comparison group. This will allow the determination of rates and risks in the perpetration of offences or victimisation, including those of a low base rate such as sexual offences. This study linked cases of children who were medically confirmed to have been sexually abused to police databases between 13 and 44 years following their abuse to determine whether victims of CSA were at increased risk of offending and victimisation than a comparison group. It should be noted that medical evidence of abuse is not available in most cases of sexual abuse (eg see Adams et al. 2003); however, in Victoria it is common practice, where possible, for children to be examined by a forensic medical officer where allegations of child sexual offending are made.

Data sources

The CSA population studied was obtained from records collected between 1964 and 1995 by the Victorian Institute of Forensic Medicine (VIFM), or its predecessor. VIFM provides forensic medical examinations for all cases of suspected CSA reported to the police to provide a medical opinion regarding whether the abuse occurred. Only cases of contact offending were included; although, as detailed below, not all children were sexually penetrated. Where it did occur, sexual penetration was operationalised as including completed, partial or attempted insertion of a penis, finger or object into an orifice where conclusively, probably or possibly indicated in the opinion provided by the doctor. The established database comprised 2,759 cases of CSA over a 31 year period, making this the largest known population of CSA victims studied. A comparison group of 2,677 people was drawn from a sample of Victorians from the Australian Electoral Commission, matched with CSA victims on gender and age range.

Offence and victimisation data for the CSA and comparison groups were obtained from the Victoria Police database in which all police contacts are recorded. Offending data included the nature and date of offence, verdict, sentence type and duration and in some circumstances, information pertaining to the victim.

Ethical approvals

Ethics approval was granted by the Monash University Standing Committee on Ethics in Research involving Humans, the Human Research Ethics Committees of VIFM and the Victoria Police Human Ethics Research Committee.

Description of childhood sexual abuse cohort

The sample included 2,759 CSA cases (2,201, 79.8% females; 558, 20.2% males), with a mean age of 10.22 years (SD=4.4) when examined and 35.58 years (SD=11.05) at follow up. All cases involved sexual contact, with 63 percent (n=1,732) including penetration (64.9% females; 55.2% males; χ2=18.06; p<0.001). Males (63.76%) were more likely than females (48.47%) to experience extra-familial abuse, χ2=24.90; p<0.001). Most (94.4%) were sexually abused by one offender, on more than occasion (62%). The follow up period from abuse to data collection ranged from 13.97 to 44.77 years (M= 25.36 years, SD=8.16).

Association between childhood sexual abuse and offending

Almost one-quarter (n=652, 23.63%) of CSA victims had a recorded offence, compared with 5.9 percent (n=157, 87 males and 70 females) of control subjects (see Table 1). The average number of charges was significantly higher for CSA cases than the comparison group (31.59 vs 19.18, t=2.11, p=<0.05) and more CSA victims (n=114, 4.1%) than controls (n=14, 0.052%) received a custodial sentence.

CSA victims were 4.97 times more likely than their peers from the general population to have been charged with an offence and this difference remained significant for both male (OR=4.34, 95% CI 3.28–5.76, p=0.000) and female (OR=6.71, 95% CI 5.17–8.71, p=0.000) victims. CSA cases were significantly more likely to be charged with all types of offences compared with the general population. Four CSA victims (2 males and 2 females) were charged with homicide, compared with no control cases. Charges with the most marked elevation among CSA cases compared with controls were sexual offences, violent offences and breach of orders.

All offences were significantly higher for both male and female CSA victims compared with their general population peers; although, the associations were stronger for female victims, with charges for threatening violence and assault being the strongest. Sexual offences, violent offences and breach of order remained most strongly associated with CSA among male victims. However, when comparing male and female CSA cases, sexually abused males were significantly more likely than their abused female counterparts to have been charged with all types of offences with the exception of homicide and prostitution.

Considering sexual offending more specifically, five percent (1 out of 20) of male CSA cases were subsequently convicted of a sexual offence, which was significantly greater than for males in the control group, of whom only 0.6 percent (6 out of 1,000) accrued a sexual offence conviction (OR=8.16, 95% CI 2.84–23.42, p=0.0001). The difference was even greater when considering boys who had been victimised at age 12 years and above, where 9.2 percent (almost 1 in 10) was subsequently found to have been convicted of a sexual offence. This was significantly greater than the rate for male CSA cases who were abused when under the age of 12 years (2.9%; OR=3.33, 95% CI 1.53–7.27, p<0.001). By contrast, for girls, there were no significant differences in the percentage who went on to be convicted of a sexual offence, regardless of whether they were abused before or after 12 years of age (0.1% or 1 out of 1,000 cases).

Association between childhood sexual abuse and victimisation

The mean number of victimisation incidents was higher for CSA cases than for the comparison group (2.94 vs 1.93, t=9.88, p=0.000). There was no significant difference in the mean number of separate sexual victimisation incidents reported (1.62 vs 1.45, t=0.86, p=0.39). Overall, CSA victims were significantly younger than the others when they were first re-victimised (range=2.93–55.26 years; M=22.73, SD=9.32 vs range=2.57–54.46 years; M=27.60, SD=9.92; t=10.94, p=0.000). However, there was no significant age difference between CSA victims and the general population when comparing the average age of first sexual (re)victimisation (16.79 vs 17.81 years, t=0.64, p=0.53).

CSA victims (36%) were 1.14 times more likely than others (33.4%) to have been victimised for any offence (p=0.000); however, this difference remained significant only for male victims (OR=1.28, 95% CI 1.01–1.61.76, p=0.038). With the exception of theft and bad public behaviour, CSA cases were significantly more likely to be victimised for all types of offences compared with the general population. Male CSA cases were significantly more likely than male comparisons to have been victimised for sexual and violent offences. Female CSA cases were significantly more likely than comparison females to report victimisation for a sexual offence, threat of violence, violence and property damage. The association for sexual victimisation was stronger for male CSA cases relative to their male peers compared with females; however, female CSA cases were significantly more likely than CSA males to be sexually re-victimised. Conversely, while male CSA cases were significantly more likely to have been a victim of violence than the CSA females, the association with being a victim of violence compared with the general population was stronger for female CSA cases.

Mediating factors between childhood sexual abuse and offending

When examining the effects of the sexual abuse variables of age at abuse (before and after 12 years of age), penetration, frequency of abuse (1 vs multiple) and number of perpetrators (1 vs multiple), upon the presence of criminal history among the CSA population, older age at abuse was found to be significant. As noted above, the strongest relationship yielded was for males sexually abused after the age of 12 years, being 3.33 times more likely than younger males to be subsequently charged with a sexual offence (95% CI 1.53–7.27, p=0.001). This remained significant even when other factors, such as severity or duration of abuse, were considered.

Discussion

Overcoming many limitations of previous studies, this study revealed that, in general, CSA victims were 1.4 times more likely to have some form of contact with the police for any matter compared with other members of the general community. Although most (77%) CSA victims did not have an official criminal record, CSA victims were almost five times more likely than others to be charged with any offence, with the strongest associations yielded for sexual and violent offences and breach of orders. It was contact with the police for being a victim of crime that accounted for a large proportion of all contacts. Nonetheless both male and female CSA victims were significantly more likely than non-abused people to be charged all types of offences, in particular violence and sexual offences. Not only were CSA victims more likely than others to offend, they had a greater number of charges, a higher proportion of charges resulting in a guilty verdict, more custodial sentences and they continued offending to an older age. These findings suggest that offences committed by sexual abuse victims are not isolated to sexual offences or being male (Benoit & Kennedy 1992).

While the majority (99%) of male and female victims of CSA were not charged for a sexual offence, CSA victims were 7.6 times more likely to be charged with sexual offences than the general population. Moreover, as the results show, a surprisingly high percentage of male victims were subsequently convicted of a sexual offence (5% of all male victims and 9.25 of those aged 12 years and above at the time of their victimisation). Some other research has found no association between childhood victims of sexual abuse and future sexual offending; however, this may be due to the small sample size of CSA victims and the fact that the samples comprised mostly females (Widom 1989a, 1989b). In a meta-analysis of factors related to recidivism in sex offenders, Hanson and Bussiere (1998) did not find a relationship between sexual abuse victimisation and subsequent sexual offending. This is, of course, due to the nature of the studies included in the meta-analysis, which have largely relied on self-report and retrospective methodology.

As expected, male CSA victims were largely responsible for the increased rate of sexual offences, in particular those boys abused at 12 years or older. Given that almost one in 10 boys who were sexually abused in this age group subsequently were convicted of a sexual offence, sexual victimisation may be an important risk factor for this population (but not for females). The hallmark feature of this period is psychosexual development, where heightened sexual arousal may be paired with cognitive distortion/implicit theories relating to sexual relations (Ward 2000) and aberrant sexual urges, which may develop and underlie sexual offending. Possible explanations for the phenomenon were not examined in this study, but should be investigated in subsequent studies.

Surprisingly, four CSA cases committed homicide compared with no control cases. Applying statistics from the wider Australian population, two or three murders per 100,000 persons would be expected— not anywhere near the 145 murders per 100,000 CSA victims revealed here. Findings also showed female victims were as likely as male victims to be charged with homicide. These findings must be interpreted cautiously given the limited sample size.

This study extends upon and lends further support to the association between CSA and re-victimisation. With the exception of theft and bad public behaviour, CSA cases were more often victims of crime than non-abused comparisons, with highest associations found for sexual offences (5x more likely), threats of violence (4x) and violent offences (3x). On average, CSA cases reported more separate victimisation incidents than the general population; however, there was no difference in the number of separate incidents relating to sexual assault. This is the first prospective study to demonstrate that male victims of CSA were significantly more likely than males in the general population, but significantly less likely than their female abused counterparts, to be a victim of a subsequent sexual assault.

These findings have a number of implications for clinical, policing and judicial practices. One clear implication is the need for therapeutic interventions targeted at adolescent male CSA victims with a focus on positive sexuality in attempt to reduce their heightened risk of committing a sexual offence. The benefits of psychological treatment for trauma, addressing victims’ mental health problems and preventing or addressing criminogenic risk factors such as low education and employment attainment, substance abuse and negative supports, in the aftermath of sexual abuse to both male and female victims is also likely to reduce the risks of offending in general and violent offences in particular. Legal and judicial representatives, as well as forensic psychologists and psychiatrists who may assess offenders, should take into consideration the complex interplay between history of CSA, mental illness and offending. Offender treatment programs in the community or custodial settings may need to be adapted to consider the role of childhood abuse in attempts to reduce recidivism. Many now do not allow for the discussion of offenders’ own sexual victimisation.

In conclusion, this is the largest prospective study to demonstrate with confidence that the majority of victims sexually abused during childhood do not perpetuate the cycle of violence by becoming an offender or by the ongoing victimisation of violence. However, relative to members of the general population, both male and female CSA victims are at an increased risk for committing or experiencing a range of offences, in particular those of a sexual or violent nature. This study also indicates that adolescent males who experience serious sexual abuse form a high-risk group for those who subsequently commit sexual offences and require active intervention and follow up.

Widom C & Maxfield M 2001. An update on the ‘cycle of violence’ (no. 184894). Washington, DC: US Department of Justice, National Institute of Justice

About the authors

Professor James Ogloff is Director of the Centre for Forensic Behavioural Science at Monash University and the Victorian Institute of Forensic Mental Health (Forensicare). Dr Margaret Cutajar is a Psychologist at Forensicare. Ms Emily Mann is a Doctoral Candidate at Monash Univeristy. Professor Paul Mullen is Emeritus Professor of Forensic Psychology, Monash University. The authors are grateful to Dr David Wells who assisted with this work. This research was funded in part by a grant from the Criminology Research Council (Grant: CRC 13/09-10).